In a wireless mobile cellular communications system, a cell edge user suffers very strong co-channel interference from a neighboring cell. Therefore, a multi-cell coordinated communications technology may be adopted to mitigate the co-channel interference.
The principle of the multi-cell coordinated communications technology is: multiple base stations (cells) communicate in a coordinated manner and serve one or more users simultaneously on a same time-frequency resource block.
At present, a base station mostly includes BBU (baseband unit)+RRU (remote radio unit). One BBU may support one or more RRUs. One RRU generally manages one cell. Therefore, the base station including BBU+RRU may manage one cell, or may manage more than one cell. Certainly, it may be considered logically that different cells are managed by different logical base stations.
Because multiple logical base stations work simultaneously in a coordinated manner on the same time-frequency resource block, joint channel correction needs to be performed on the multiple logical base stations (that is, multiple RRUs) involved in the multi-cell coordinated communications. At present, technologies for receive channel self-correction and transmit channel self-correction of a single base station (that is, a single RRU) are already mature. However, joint channel correction among multiple cells is still in research now.